Elevator safety appliance.



L. LEWANDOWSKI.

ELEVATOR SAFETY APPLIANCE.

APPLICATION FILED DEILZ. i916. 1,238,414, y PamedAug. 28,1917.

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L LEWANDOWSKI ELEVATORVSAFETY APPLIANCE.

APPLlcmlov FILED DEC. 26. me.

Patented Ang. 28, 1917.

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UNITED STATES PATENT OFFICE.

LEON LEWANDOWSKI, OF DETROIT, MICHIGAN, ASSIGNOR OF ONE-HALF TO ANTHONY S. FIJALKOW-SKI, OF DETROIT, MICHIGAN.

ELEVATOR SAFETY APPLIANCE.

Application filed December 26, 1916.

To all whom t may concern.'

Be it known that I, LEON LnwANDowsnr, citizen of the United States, residing at Detroit, county of lVayne, State of Michigan, have invented a certain new and useful Improvement in Elevator Safety Appliances, and declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the same, refer'- encebeing had to the accompanying drawings, which form a part of this specification.

My invention relates to an elevator safety appliance shown in the accompanying drawings and more particularly set forth in the following specification and claims.

One object of my invention is to provide a device adapted to become instantly operative upon the hoisting cable breaking or slackening;-the construction being such as to prevent the rack bars attached to the guide rails of the elevator spreading with reference to a plurality of eccentric gears,

carried by the elevator, and thus failing to coperate to stop the descent of the elevator as a result of an accident to the hoisting cable.

Another object of the invention is to provide means for absorbing the shock which might be felt in the elevator cab upon the sudden stoppage of the latter due to the 0peration of the device.

Other advantages and improvements will hereafter appear as the description proceeds it being understood that changes may be made in the precise embodiment of the invention as herein described and shown, without departing from the spirit of the same.

In the drawings accompanying this specitication:

Figure l is an elevation of the elevator cab, the movable frame in which it is suspended, a fragment of the guide rails and rack bars, the coperating eccentric gears and mechanism relating thereto.

Fig. 2 is an elevation at right angles to Fig. l showing the double form of rack bar, the eccentric coperating gears, and gears by which the latter are rotated into locked meshed relation with the rack bars.

Fig. 3 is plan-sectional view on line 3 3 of Fig. l, of a detail of construction.

Fig. 4 is a cross sectional view of a de- Specicaton of Letters Patent.

Patented Aug. 28, 191 7. Serial No. 138,887.

tail` taken on line 4-4 of Fig. 1, as viewed in the direction indicated by the arrow.

Fig'. 5 is a sectional view of a detail of construction, taken on line 5 5 of Fig. 4'.

Referring now to the letters of reference placed upon the drawings,

A, denotes an elevator cab, suspended in an inclosing traveling frame B, by a plurality of springs C. The frame includes upper and lower pairs of bearing blocks B and B2. D, denotes the usual guide rails of an elevator well. E, indicates rack bars bolted to each side of the guide rails. F denotes shafts journaled in the upper bearing blocks of the frame B, above the elevator cab. on which are respectively mounted intermeshing gears G. H, designates eccentric gears mounted on each end of the respective shafts F, normally out of mesh with the rack bars located between the gears.

I, designates a hoisting cable and I', and I2, are cables connected with the hoisting cable,-their lower ends being respectively wound upon the shafts F, to which they are secured.

J, designates a spring coiled upon the shaft F, having one end engaged with the shaft and the other end with the frame B, the action of which is to rotate the eccentric gears, through the gears G, into meshed locking relation with the rack barswhen released from the control of the cables I', and I2. K, denotes a pair of shafts journaled in the lower pairs of bearing blocks B2 of the frame B, beneath the elevator cab, upon the ends of which are mounted eccentric gears L, normally out of mesh with the rack bars E, but which are adapted to be rotated into mesh therewith in a. manner similar to the eccentric gears H, upon the breaking of the hoisting cable.

M, designate intermeshing gears carried by the respective shafts K. N, is a spring sleeved upon one of the shafts,-one end of which is secured to the shaft and the other end engaged to the frame B; the purpose of the spring being to rotate the eccentric gears L, through the gears M, into mesh with the rack bars when released from the control of the cable O, connecting one of the shafts F, with one of the shafts K;- the ends of the cable being wound upon the respective shafts and secured thereto.

Having indicated the several parts by reference letters the construction and operation of the apparatus will be readily understood.

Upon the hoisting cable breaking, or slaclening sufficiently to permit the resilient action of the spring J, to become effective, the shaft F, on which it is mounted is rotated causing the gear G, intermeshing with its corresponding gear on the other shaft F, to rotate the respective eccentric gears H, carried by said shafts into intermeshing locking relation with the rack bars E. Simultaneously with the operation of the eccentric gears TLT-the eccentric gears L, located beneath the cab will be forced into intermeshing locking relation with the rack bars, through the release of the connecting cable O, controlling the operation of the spring `i\l;-the resilient action of which serves to rotate the shaft K, and thereby the intermeshing gears M, controlling the operation of the several eccentric gears L, into mesh with the rack bars, in a similar manner to that of the gears H,-as will be readily understood.

It will be noted that a partial rotation of the several eccentric gears will serve to grip the rack bars and thus arrest the further descent of the cab and that the danger which might otherwise result from the rack bars spreading with reference to the teeth of the eccentric gears is overcome through the opposing application of the gears upon the intermediate rack bars.

To absorb the shock that might otherwise result from the sudden operation of the device, the cab A, is yieldingly suspended in the traveling frame B, by the springs C;- the action of which will be clearly understood without further explanation.

Having thus described my invention what I claim is l. A safety elevator, comprising a traveling frame, guide rails therefor, a cab yieldably supported by the traveling frame, oppositely disposed bars, a pair of eccentric members for each bar, the members of each pair being disposed upon opposite sides of the eoperating bar, connecting means between the pairs of eccentric members to cause synchronous action thereof, means normally tending to cause the eccentric mem- Cones of this patent may be obtained bers to grip the bars, a hoisting cable connected directly with the cab, and other connections between the hoisting cable and the said eccentrics to normally hold said eccentrics free of the bars.

2. A safety elevator, comprising a traveling frame, a cab mounted upon the traveling frame, upper and lower yieldable connections between the cab andvframe, opposed bars, upper and lower pairs of eccentric members mounted upon the frame and disposed to coperate with the said bars, connecting means between the respective upper and lower pairs of eccentric members to cause synchronous movement thereof, means associated with the upper and lower eccentric members normally tending to cause them to grip the said bars, a hoisting cable connected with the cab, connecting means between the hoisting cable and one of the eccentric member connecting means to hold said eccentric members free of the bars under normal conditions, and means connecting the upper and lower eccentric member connecting means.

3. A safety elevator comprising a traveling frame, guide rails therefor', rack bars upon the guide rails, upper and lower pairs of shafts mounted upon the traveling frame, pairs of eccentric gears at opposite ends of the respective pairs of shafts disposed upon opposite sides of the rack bars to engage the same under abnormal conditions, connecting means between the respective pairs of shafts to cause them to operate in unison, means normally tending to throw the pairs of eccentric gears into operative engagement with the rack bars, a cab yieldably mounted in the traveling frame, a hoisting cable connected with the cab, connecting means between the hoisting cable and onevpair of the said pairs of shafts to hold the eccentric gears clear of the yrack bars under normal conditions, and connecting means between the two pairs of shafts to hold the remaining eccentric gears out of engagement with the rack bars under normal conditions.

In testimony whereof, I sign this speciication in the presence of two witnesses.

LEON LEWANDOWSKI.

Witnesses:

A. S. FIJALKOWSKI, S. E. THOMAS.

for ve cents each, by'addressing the Commissioner of Patents,

Washington, D. C. 

